Adtran TRC5045L1 Manual Do Utilizador

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Section 6  Troubleshooting Guide
TRACER 5045 System Manual
 54
© 2003 ADTRAN, Inc.
612805045L1-1A
5.
INSTALLING/TROUBLESHOOTING THE TRACER HARDWARE
1. Perform a detailed path profile and link budget for each TRACER 5045 microwave link. A 
thorough path study can be used to estimate signal power budgets, fade margins at each receiver, 
identity potential line-of-site obstacles, properly size antenna dishes, and determine minimum 
antenna dish heights above the earth.
2. Setup all of the TRACER hardware on a workbench. ADTRAN recommends that the actual cables 
used in the permanent installation be used in the workbench setup. A rigorous workbench 
“simulation” of the link will help alleviate and avoid time-consuming errors.
3. Examine the 
PLAN A
 and 
PLAN B
 LEDs on the front panel of each unit. These LEDs indicate the 
frequency plan for each TRACER 5045 unit. The frequency plan (Plan A, Plan B) LED should be 
the opposite on the TRACER 5045 units. 
4. Attach the RF coaxial cables to be used in the permanent installation to the N-type connectors on 
the back of the TRACER 5045 unit. Attach the other end of the coaxial cable(s) to an RF power 
meter or spectrum analyzer, if either is available. The power measured by the meter/analyzer will 
be the RF power available at the input of the antenna. The TRACER 5045 unit is programmed at 
the factory to output approximately 100 mW (20 dBm) of RF power. The actual power level 
measured by the meter/analyzer will be less than 100 mW due to RF losses through the coaxial 
cable, and is a function of the cable type and length being used. In any event, the power level at the 
output of the coaxial cable should be a significant fraction of 100 mW. A power meter/analyzer 
reading that is not on the order of at least tens-of-milliwatts could be an indication of any 
combination of either unsuitable RF, faulty, or unreasonably long coaxial cable.
5. Resolve all RF coaxial cabling errors before proceeding.
6. Attach the RF coaxial cables to a high-quality attenuator, if possible. If you do not have an 
attenuator, attach the coaxial cables to the antennas to be used in the permanent installation. If the 
installation antennas are not available, small, inexpensive dipole or patch antennas can be used for 
verification purposes. If an adjustable attenuator is being used, dial in the amount of attenuation 
that corresponds to the path loss value expected for the microwave link in which the TRACER 
hardware will be installed. The path loss value can be calculated from a knowledge of the path 
length, or provided by a path study. Remember to subtract both antenna gain values from the 
attenuator level if these values have not already be accounted for.
7. After setting up the RF pieces, examine the 
RF DOWN
 LED on the front panel of each TRACER 
5045 unit. If the 
RF DOWN
 LED is illuminated (red), the corresponding TRACER 5045 is not 
receiving a suitable RF signal from the other TRACER 5045 unit. In this case, the receiving 
TRACER 5045 is either receiving a very weak signal, or no signal at all. If the 
RF DOWN
 LED is 
not illuminated, then the TRACER 5045 units are receiving a suitable RF signal. Suitable RF 
power levels for low error rate communication will range from -30 dBm to -78 dBm measured at 
the N-type connector input on the TRACER 5045 unit.
8. Resolve any signal level issues before proceeding.
ADTRAN provides a wireless link planning tool on our website. This link budget tool is 
constructed as an easy to use spreadsheet with dropdown menus so that the user can 
quickly change any of the link parameters (antenna size, coaxial cable type and length, 
frequency band, link distance, etc) and instantly see how the microwave path availability is 
affected. This tool is available at
 and can be used online or 
downloaded for standalone use.